SEASONAL PREVALENCE AND MULTIDRUG RESISTANCE IN ISOLATES OF 11 SALMONELLA SPECIES IN NASARAWA STATE, THE NORTH CENTRAL ZONE OF NIGERIA

The emergence of multi-drug resistant strains of Salmonella typhi and Salmonella paratyphi is the most challenging aspect of typhoid treatment in the therapeutic scenario. This study was carried out to determine the seasonal prevalence and multidrug resistant S’, typhi and S. paratyphi isolates in Nasarawa state, Nigeria. A total of 1200 stool samples were collected from typhoid fever patients, and typhoid bacteria were isolated using standard microbiological methods and tested for their susceptibility to 8 commonly used antibiotics. Of this, 599(49.9%) samples showed significant bacterial growth in which S. typhi and S. paratyphi were 260(21.7%) and 339(28.3%) respectively. Seasonal isolation rate in the study showed Salmonella species infection occurring throughout the year and was associated with geographical zones (P<0.05). Seasonal isolation was highest in the month of April (early month of the rainy season) with the Western geographical zone of the state having the highest prevalence. There was a significant difference (P<0.05) among the isolates in terms of their susceptibility from the 3 geographical zones of the state. Isolates were highly susceptible to Amikacin, Ciprofloxacin, Gentamycin, Chloramphenicol and Ceftriaxone and highly resistant to Amoxycillin, Amoxycillin/clauvulinic acid, and Teteracycline. Most of the isolates were multidrug resistant and were significantly associated with geographical zones (P<0.05). For example, 36.8%, 43.6%, and 34.7% in the Northern, Southern, and Western geographical zones were resistant to four (4) antibiotics respectively. Improvement of safe water supply, intensive health education and public health measures particularly on issues such as improving personal and food hygiene and hand washing were recommended.